import java.util.Scanner;

public class Scorestat {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.println("STB的成绩是：");
        int stb = scanner.nextInt();
        int java = scanner.nextInt();
        int sql = scanner.nextInt();
        int sum = stb + java + sql;
        double avg = sum / 3.0;
        int diffen = java - sql;
        System.out.println("java和sql成绩差：" + diffen);
        System.out.println("平均分：" + avg);


    }
}
